One of the most effective ways to change an attitude is to start behaving as if you already feel and think the way you'd prefer to.

改变一种态度最有效的方法之一就是开始用以你喜欢的方式去感受和思考。

youdao

If you want to pass your exams you'd better change your attitude!

你若想通过考试就最好改变你的态度！

《牛津词典》

As a matter of fact, change your attitude and you will change your world.

事实上，改变你的态度，你就能改变自己的世界。

youdao

The bottom line is this: you may not be able to change your situation overnight, but you can change your attitude about it.

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No matter what the reason is for the sudden change in your job responsibilities, you need to maintain a positive attitude, talk to your supervisor and refrain from complaining, among other thing.

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